The study identifies forms of unconventional insertion into the labour market of Natal (RN). A research was conducted, involving eight districts selected under previously defined criteria, such as low income and the existence of favelas (slums). The available literature on the subject was reviewed, in an attempt to establish a definition of categories of workers; to reach this objective, the authors readapted a methodological scheme suggested by Lucio Kowarick. Accordingly to the specific features of the situation under analysis, it has been possible to identify autonomous workers and odd-jobbers (59%) intermittent workers (17,3%) and informal productive units (22%), the latter subdivided into arts of workmanship and home industrial arts, small established trade units and productive units for the rendering of services. As to the type of suitable policies to be implemented in the informal sector, and effort was made to alleviate the controversy on the subject thought the presentation of a few suggestions. Special prominence received the various modalities of informal productive units, an aspect which, due to the peculiarities of the northeastern economy, requires a more detailed study as atypical units that should get support from governmental agencies, among them the Cebrae (Centro Brasileiro de Apoio à Pequena e Média Empresa - Brazilian Center for Support of Small and Medium-Sized Enterprise) itself.Formas de inserção informal no mercado de trabalho. Revisão de literatura sobre o assunto. Identificação de categorias de trabalhadores. Tipos de políticas passíveis de implementação. Unidades produtivas informais.